E_STREAM_ERROR: CURL returned 35 (23)

I had this error trying to load ebooks from kobo into Aldiko 3.1.3 on an android phone. One day it was working, the next day not.

Eventually, I gave up - there are no clues on line that I could find and Aldiko is very old now. There's a Aldiko Next, but it doesn't have facility to attach an Adobe DRM account so it's useless. 

What I did in the end was I removed the permission for Aldiko to access URLs as a default, so every time I get the choice of Aldiko or Adobe Digital Editions as the app to open the download from Kobo. ADE then downloads the e-pub fine. Then, in Aldiko, add books from file, find the e-pub where it's stashed by ADE and import it into Aldiko.

So it looks like the download from kobo into Aldiko is broken, but it can still open the DRM epubs from kobo if you can download them via ADE. Hope that helps someone.